Nancy Caroline’s Emergency Care in the Streets, Seventh Edition
Chapter 31: Soft-Tissue Trauma
Chapter 31
Soft-Tissue Trauma
Unit Summary
This chapter provides information on one of the most common types of traumatic injuries prehospital providers will be confronted with. The skin is the largest organ of the human body and serves as the interface between the body and the outside world. For that reason, injuries involving the skin are common. Injuries to the skin are often the most obvious of a person’s injuries, although not necessarily the most serious. You can avoid making a critical mistake by ensuring that you have a thorough understanding of the anatomy and physiology of the skin.
National EMS Education Standard Competencies
Trauma
Integrates assessment findings with principles of epidemiology and pathophysiology to formulate a field impression to implement a comprehensive treatment/disposition plan for an acutely injured patient.
Soft-Tissue Trauma
Recognition and management of
• Wounds (pp 1547–1549, pp 1554–1567)
• Burns (see chapter, Burns)
• Electrical (see chapter, Burns)
– Chemical (see chapter, Burns)
– Thermal (see chapter, Burns)
• Chemicals in the eye and on the skin (see chapters, Diseases of the Eyes, Ears, Nose, and Throat and Burns)
Pathophysiology, assessment, and management of
• Wounds
– Avulsions (p 1562)
– Bite wounds (pp 1563–1564)
– Lacerations (p 1560)
– Puncture wounds (pp 1560–1562)
– Incisions (p 1560)
• Burns
– Electrical (see chapter, Burns)
– Chemical (see chapter, Burns)
– Thermal (see chapter, Burns)
– Radiation (see chapter, Burns)
• High-pressure injection (pp 1566–1567)
• Crush syndrome (pp 1565–1566)
Knowledge Objectives
- Discuss the anatomy and physiology of the skin, including the layers of the skin. (pp 1545–1547)
- Understand the functions of the skin, and its role in the inflammatory process. (pp 1545–1547)
- Discuss the pathophysiology of soft-tissue injuries, including closed injuries, open injuries, and crush injuries. (pp 1547–1549)
- Discuss the process of wound healing, including hemostasis, inflammation, epithelialization, neovascularization, and collagen synthesis. (pp 1549–1550)
- Explain skin tension lines and how they relate to wound healing. (p 1547)
- Discuss alterations in the wound healing process, including anatomic reasons, high-risk wounds, abnormal scar formation, pressure injuries, and wounds requiring closure. (pp 1549–1550)
- Discuss the pathophysiology of wound healing, including infection, gangrene, tetanus, and necrotizing fasciitis. (pp 1550–1551)
- Describe the assessment process for patients with a soft-tissue injury, with a focus on when to perform a physical exam. (pp 1551–1554)
- Describe the relationship between airway management and the patient with closed and open injuries. (p 1552)
- Discuss emergency medical care of a patient with a soft-tissue injury. (pp 1554–1560)
- Discuss the principles for treating a closed wound. (p 1554)
- Discuss the principles for treating an open wound. (p 1554)
- List the steps in controlling external bleeding. (pp 1556–1558)
- List the steps for applying a tourniquet. (pp 1557–1558)
- Understand the functions and types of sterile dressings and bandages. (pp 1558–1560)
- Discuss methods and materials for site-specific dressings. (pp 1554–1555)
- Describe complications of improperly applied dressings. (pp 1555–1556)
- Discuss the role of pain control when managing patients with soft-tissue injuries. (p 1558)
- Discuss the pathophysiology, assessment, management of abrasions, lacerations, puncture wounds, impaled objects, avulsions, amputations, animal and human bites, crush syndrome, compartment syndrome, and high-pressure injection. (pp 1560–1567)
Skills Objectives
- Demonstrate the assessment and management of a patient with signs and symptoms of soft-tissue injury, including:
a. Contusion (p 1554)
b. Hematoma (p 1554)
c. Abrasion (p 1560)
d. Laceration (p 1560)
e. Puncture wound (pp 1560–1562)
f. Impaled object (pp 1560–1562)
g. Avulsion (p 1562)
h. Amputation (pp 1562–1563)
i. Animal and human bites (pp 1563–1564)
j. Crush syndrome (pp 1565–1566)
k. Compartment syndrome (p 1566)
l. Blast injuries (p 1549 and see chapter, Trauma Systems and Mechanism
of Injury)
m. High-pressure injection injuries (pp 1566–1567)
- Describe the method for controlling bleeding from a soft-tissue injury. (pp 1556–1558)
- Describe the method for applying a tourniquet. (pp 1557–1558)
Readings and Preparation
Review all instructional materials including Chapter 31 of Nancy Caroline’s Emergency Care in the Streets, Seventh Edition, and all related presentation support materials.
Support Materials
• Lecture PowerPoint presentation
• Case Study PowerPoint presentation
Enhancements
• Direct students to visit the companion website to Nancy Caroline’s Emergency Care in the Streets, Seventh Edition, at http://www.paramedic.emszone.com for online activities.
• Web link
o The National Library of Medicine contains good information on crush injuries and compartment syndrome that students can use as a reference for assignments: http://www.nlm.nih.gov
Content connections: Soft-tissue injuries can be related to all of the anatomy and physiology sections of Nancy Caroline’s Emergency Care in the Streets, Seventh Edition, and all related presentation support materials.
Cultural considerations: It may be difficult to determine closed soft-tissue injuries in darkly pigmented skin using visualization alone. A thorough assessment and history is essential in all skin types.
Teaching Tips
Soft-tissue injuries are one of the most common types of injuries seen in prehospital care; however, there is a tendency among providers to diminish the importance of this type of injury. Discuss the potential effects of soft-tissue injuries with students to emphasize the importance of a thorough assessment.
Unit Activities
Writing activities: Direct students to prepare a written assignment on the topic of compartment syndrome. Students should include a discussion of how this condition develops and how it is treated. You may suggest students visit the AAOS website for additional information regarding compartment syndrome, at http://orthoinfo.aaos.org/topic.cfm?topic=A00204.
Student presentations: Students may present the results of their written assignment or group activity to the class.
Group activities: Divide students into four groups. Direct students to discuss one of the steps in RICE (Rest, Ice, Compression, Elevation) as it relates to a soft-tissue injury. Students should include a discussion of how this type of treatment affects the injury.
Visual thinking: Provide students with a cross-section diagram of the skin. Have students visually demonstrate how a blunt injury causes ecchymosis.
Pre-Lecture
You are the Medic
“You are the Medic” is a progressive case study that encourages critical-thinking skills.
Instructor Directions
Direct students to read the “You are the Medic” scenario found throughout Chapter 31.
• You may wish to assign students to a partner or a group. Direct them to review the discussion questions at the end of the scenario and prepare a response to each question. Facilitate a class dialogue centered on the discussion questions and the Patient Care Report.
• You may also use this as an individual activity and ask students to turn in their comments on a separate piece of paper.
Lecture
I. Introduction
A. The skin is the largest organ of the human body.
1. Serves as interface between the body and outside world
a. Injuries involving the skin are common.
i. Often most immediately obvious of injuries
ii. Not necessarily the most serious of injuries
b. Do not neglect to check for higher-priority problems because of dramatic-looking skin injuries.
2. A wound is any injury to the soft tissues with or without involvement of subcutaneous tissues and muscle.
a. Generally low-priority injuries unless they:
i. Compromise the airway
ii. Are associated with massive bleeding
b. Always search systematically for other injuries or life-threatening conditions before treating soft-tissue trauma.
c. Do not let dramatic soft-tissue injuries distract you from conducting a thorough primary assessment.
II. Incidence, Mortality, and Morbidity
A. The body’s soft tissues can be injured through a variety of mechanisms.
1. Blunt injury—energy exchange between patient and object is more than tissues can handle.
a. Example: A person’s head hitting the steering wheel during an automobile crash
2. Penetrating injury—an object (eg, bullet or knife) breaks through the skin into the body, causing an entrance wound and possibly an exit wound.
3. Burns—may cause soft-tissue injuries.
B. Soft-tissue trauma is the leading form of injury.
1. Open wounds cause approximately 6.5 million ED visits.
a. Nearly 5 million patients present with contusions.
b. Most require basic interventions.
i. Wound irrigation
ii. Dressing
iii. Bandaging
iv. Limited suturing
C. Death from soft-tissue injury is extremely rare, and typically related to hemorrhage or infection.
1. Uncontrolled bleeding can lead to shock and death
2. In open wounds, invading pathogens can cause local or systemic infection.
a. Can be limb or life threatening
i. Especially in patients with diabetes
3. Preventing soft-tissue injuries involves simple protective actions.
a. Use of gloves when working with abrasive materials
b. Use of safety devices on machines
c. Teaching children to avoid using sharp objects
i. Plastic scissors, knives, and drinking cups are designed to reduce risk of injury to children.
III. Structure and Function of the Skin
A. Skin, or integument, is a complex organ with a crucial role in maintaining the constancy of the internal environment (homeostasis).
1. Protects underlying tissue from injury, including those caused by:
a. Temperature extremes
b. Ultraviolet radiation
c. Mechanical forces
d. Toxic chemicals
e. Invading microorganisms
2. Aids in temperature regulation
a. Prevents heat loss when core body temperature starts to fall
b. Causes heat loss when core temperature rises
3. Prevents excessive water loss from the body and drying of the tissues
4. Acts as a sense organ
a. Sense receptors in the skin mediate:
i. Changes in temperature
ii. Touch
iii. Body position
iv. Pain sensation
5. Significant skin damage may make the patient vulnerable to:
a. Bacterial invasion
b. Temperature instability
c. Fluid balance disturbances
B. Epidermis
1. The skin is composed of two layers.
2. The epidermis (outer layer) is the first line of defense.
a. Principle barrier against:
i. Water
ii. Dust
iii. Micro-organisms
iv. Mechanical stress
b. It consists of five layers:
i. Stratum corneum: Outermost layer of hardened, nonliving cells that shed through the process of desquamation
ii. Four inner layers of living cells that divide to give rise to the cells of the stratum corneum
(a) Contain variable number of cells called melanocytes that contain melanin granules.
(1) The skin’s darkness is directly related to the amount of melanin present.
C. Dermis
1. The dermis (inner layer) is a tough, highly elastic layer of connective tissue.
2. Composed mostly of:
a. Collagen fibers
b. Elastic fibers
c. Mucopolysaccharide gel
d. Fibroblasts, which secrete:
i. Collagen: Fibrous protein with high tensile strength
(a) Gives high resistance to breakage under mechanical stress
ii. Elastin allows skin to spring back in place.
iii. Ground substances: Transparent mucopolysaccharide gel that gives skin resistance to compression
3. Dermis is subdivided into:
a. Papillary dermis
i. Provides nutrients to the epidermis
ii. Aids in thermoregulation
iii. Dilation increases blood flow to skin, allowing heat to dissipate
iv. Constriction results in heat retention
b. Reticular layer
i. Dense, irregular connective tissue provides strength and elasticity
4. Dermal layer also has macrophages and lymphocytes
a. Part of the inflammatory process
b. Responsible for combating microorganisms that breach the epidermal layer
i. Will destroy invading microorganisms
ii. Signal other cells to migrate into the area
iii. Physical injury will cause mast cells to degranulate and create special chemical mediators.
(a) Results in increased blood flow to area, manifesting as redness and warmth
5. Specialized structures in the dermis include:
a. Nerve endings
i. Mediate the senses of:
(a) Touch
(b) Temperature
(c) Pressure
(d) Pain
b. Blood vessels
i. Carry oxygen and nutrients to the skin.
ii. Remove CO2 and waste products.
iii. Cutaneous blood vessels help regulate body temperature by regulating blood flow volume from the body’s core to its surface.
c. Sweat glands
i. Produce sweat and send it through ducts to the skin surface.
(a) Sweat consists of water and salts.
(b) Regulated through the sympathetic nervous system
ii. Average sweat loss:
(a) During normal conditions between 500 and 1,000 mL in 24 hours
(b) During strenuous exercise up to 1,000 mL per hour
iii. Water evaporation from skin surface is a major mechanism for shedding heat.
d. Hair follicles
i. Produce hair and enclose hair roots
ii. Each follicle contains a single hair.
iii. Attached to a small muscle that when contracted causes the follicle to assume a more vertical position
iv. Definite periods of growth for hair in each part of the body, after which they are shed and replaced
e. Sebaceous glands
i. Located at the neck of each hair follicle
ii. Secretory mechanism that creates an oily substance called sebum
(a) Secretions empty into hair follicles to reach skin surface.
D. Subcutaneous tissue
1. Layer beneath the dermis (superficial fascia)
a. Consists mostly of adipose tissue (fat), along with:
i. Blood vessels
ii. Lymph vessels
iii. Hair follicle roots
b. Subcutaneous fat:
i. Insulates underlying tissues from hot and cold extremes
ii. Provides a cushion for underlying structures
iii. Provides an energy reserve for the body
E. Deep fascia
1. A thick, dense layer of fibrous tissue below the subcutaneous tissue
2. Composed of tough tissue bands that cover muscles and other internal structures
3. Supports and protects underlying structures
a. Muscles and bones are located below this layer.
F. Skin tension lines
1. Skin is arranged over body structures in a way that creates tension
a. Varies by body region
b. Occurs in patterns known as tension lines
2. Static tension develops over areas with limited movement (for example, the scalp)
a. Lacerations occurring parallel to skin tension lines may remain closed
b. Larger wounds may be pulled open and require closure.
c. Small lacerations lying perpendicular to tension lines result in wounds that remain open.
i. Healing is slower in an open wound.
ii. Scarring is more likely.
3. Dynamic tension is found over muscle.
a. Tension varies according to muscle contraction and subsequent skin movement.
b. Open injuries interfere with healing because they:
i. Disrupt the clotting process
ii. Disrupt the tissue repair cycle
4. An abnormal scar may prompt scar revision surgery.
a. Surgeon takes skin tension into account when choosing the revision procedure.